Test tubes have long been used for collecting and handling specimens of various types to be tested for a variety of reasons. Of course, errors in testing are never desirable, but in certain types of testing such as diagnostic testing of a person's blood, errors are not only undesirable but can have disastrous consequences. Moreover, testing errors can take a variety of forms resulting from other than a failure to perform the test procedures correctly. For example, a test properly performed on the wrong specimen can lead to erroneous results, either by associating proper test results with the wrong patient, or obtaining faulty test results due to the wrong additive being present in the specimen being tested.
As a result, it is not surprising that health care and testing facilities take great caution in properly identifying each specimen in order to prevent misidentification or mistaken testing of any specimen.
For example, when various blood tests are desired in the diagnosis and/or treatment of patients, a phlebotomist is typically given a list of blood draws that need to be collected with the associated tests that need to be performed. The phlebotomist then enters a patient room in the hospital, nursing home, clinic and so on to perform a blood draw, often with a stack of 30 patient labels and a variety of color coded and labeled test tubes such as shown in FIG. 1. For example, blood drawn for a certain test will be drawn into a test tube 10 with a specific color cap 12 and base label 14, whereas blood for testing requiring a particular additive may be drawn into a test tube having the additive and identified by a cap and base label having a different identifying color.
The phlebotomist will go from patient to patient, performing the required blood draw for each patient, in each case adding the secondary (patient identifying) label to the tube(s) containing that patient's blood. Depending on the facility, the completed test tubes may be sent to the laboratory in batches to be processed. Once in the lab, the test tubes may be placed in a robotic rack with the label (typically including a barcode) scanned for identification purposes, and a myriad of tests then performed based on that identification. When in a robotic application site, verification of the tube contents is critical without the use of human intervention.
In those cases in which the lab is not robotic, however, the labeled and closed tubes 10 are placed in a rack and wait for a technician to cycle and perform the tests. In certain stations of testing, the lab technicians may be required to siphoned off (pour off) blood from the tubes 10 to perform other tests. This allows the number of blood draws required from the patients to be minimized, and in some instances is necessary in order to leverage time sensitive tests due to fasting, glucose and so on. In such situations, the technician will typically take the cap 12 off the test tube 10 and then place the tube 10 back in the rack, often with several other samples be in the rack. However, if the secondary label has covered up the entire base label 14, the technician may not be able to see the type of tube that was used (since the color identifying cap 12 is removed, and the color identification on the base label 14 is covered up). In such cases, the technician must peel back the secondary label to try and expose the color identification of the base label 12, which peeling of the label may destroy the base label 12 and make it impossible to see the color identification.
In order to address this concern and also to ensure in robotic applications that the secondary labels are properly aligned (so that their bar code may be properly read to identify the tube), solutions have been sought which attempt to ensure that the secondary label is properly positioned on the test tube (e.g., by placing guide markings on the base labels). In such cases, the lab technician may be required to remove the tube from the line and either (1) remove the label (if possible) and reposition it; or (2) reprint the label, both of which result in wasted time. Further, while proper alignment of the secondary label may protect against the base label being covered up by the patient identifying secondary label, the fact remains that secondary labels are applied often in haste, often by a phlebotomist holding several things at once, and experience has shown that 6%-8% of such labels are commonly misaligned when applied. Therefore, despite such attempts to ensure that the base label 12 is not covered, the previously discussed problems at manual testing sites still arise.
The present invention is directed toward overcoming one or more of the problems set forth above.